*2Recently, a nitride semiconductor such as gallium nitride (GaN) is in the limelight as an important material for an electronic device and a photoelectric material because of its superior physical and chemical characteristics. Particularly, the development of highly efficient light-emitting diodes (LEDs) of primary colors (Red, Blue, Green) and white color expands an application area of a light-emitting diode. For example, the LED has been applied to a variety of fields such as a keypad, a backlight of a liquid crystal display device, a traffic light, a guide light of a runway in an airport and a lighting apparatus.
FIG. 1 is a sectional view illustrating a related art light-emitting device. The related art light-emitting device includes a sequentially formed an n-type GaN layer 12, an active layer 13, and a p-type GaN layer 14. Portions of the p-type GaN layer 14, the active layer 13, and the n-type GaN layer 12 are removed using etching to expose a portion of an upper surface of the n-type GaN layer 12. A p-type electrode 15 is formed on an upper surface of the p-type GaN layer 14 and an n-type electrode 16 is formed on the exposed upper surface of the n-type GaN layer 12.
The above described light-emitting device is applied to a variety of fields as a highly efficient light source. However, the related art light-emitting device is very susceptible to an electric shock such as a static electricity. In other words, an electrostatic discharge (ESD) generated in reverse bias in the light-emitting device may damage an internal physical structure of the light-emitting device.
In addition, because the related art ESD-protection device occupies a relatively large area, light efficiency of the light-emitting device is decreased.
Furthermore, because the addition of the ESD-protection device increases a size of the light-emitting device, it is difficult to apply the light-emitting device to a subminiature, ultra-thin and ultra-lightweight package.